Buggy code:
private static final String forwardHistoryActionDefId = "org.eclipse.ui.navigate.forwardHistory" ; private final WorkbenchWindow window ; private final IPropertyChangeListener propertyChangeListener = new IPropertyChangeListener ( ) { public void propertyChange ( PropertyChangeEvent event ) { } } ; private NewWizardAction newWizardAction ; private NewWizardDropDownAction newWizardDropDownAction ; private NewWizardMenu newWizardMenu ; private CloseEditorAction closeAction ; private CloseAllAction closeAllAction ; private CloseAllSavedAction closeAllSavedAction ; private ImportResourcesAction importResourcesAction ; private ExportResourcesAction exportResourcesAction ; private GlobalBuildAction rebuildAllAction ; private GlobalBuildAction buildAllAction ; private SaveAction saveAction ; private SaveAllAction saveAllAction ; private AboutAction aboutAction ; private OpenPreferencesAction openPreferencesAction ; private QuickStartAction quickStartAction ; private TipsAndTricksAction tipsAndTricksAction ; private SaveAsAction saveAsAction ; private ToggleEditorsVisibilityAction hideShowEditorAction ; private SavePerspectiveAction savePerspectiveAction ; private ResetPerspectiveAction resetPerspectiveAction ; private EditActionSetsAction editActionSetAction ; private ClosePerspectiveAction closePerspAction ; private LockToolBarAction lockToolBarAction ; private CloseAllPerspectivesAction closeAllPerspsAction ; private PinEditorAction pinEditorAction ; private ShowViewMenuAction showViewMenuAction ; private ShowPartPaneMenuAction showPartPaneMenuAction ; private CyclePartAction nextPartAction ; private CyclePartAction prevPartAction ; private CycleEditorAction nextEditorAction ; private CycleEditorAction prevEditorAction ; private CyclePerspectiveAction nextPerspectiveAction ; private CyclePerspectiveAction prevPerspectiveAction ; private ActivateEditorAction activateEditorAction ; private WorkbenchEditorsAction workbenchEditorsAction ; private RetargetAction undoAction ; private RetargetAction redoAction ; private RetargetAction cutAction ; private RetargetAction copyAction ; private RetargetAction pasteAction ; private RetargetAction deleteAction ; private RetargetAction selectAllAction ; private RetargetAction findAction ; private RetargetAction addBookmarkAction ; private RetargetAction addTaskAction ; private RetargetAction printAction ; private RetargetAction revertAction ; private RetargetAction refreshAction ; private RetargetAction propertiesAction ; private RetargetAction moveAction ; private RetargetAction renameAction ; private RetargetAction goIntoAction ; private RetargetAction backAction ; private RetargetAction forwardAction ; private RetargetAction upAction ; private RetargetAction nextAction ; private RetargetAction previousAction ; private RetargetAction buildProjectAction ; private RetargetAction rebuildProjectAction ; private RetargetAction openProjectAction ; private RetargetAction closeProjectAction ; private NavigationHistoryAction backwardHistoryAction ; private NavigationHistoryAction forwardHistoryAction ; public WorkbenchActionBuilder ( IWorkbenchWindow window ) { } protected WorkbenchWindow getWindow ( ) { } public void buildActions ( ) { } private void hookListeners ( ) { } private void enableActions ( boolean value ) { } private void fillMenuBar ( ) { } private MenuManager createFileMenu ( ) { } private MenuManager createEditMenu ( ) { } private MenuManager createNavigateMenu ( ) { } private MenuManager createProjectMenu ( ) { } private MenuManager createWindowMenu ( ) { } private void addPerspectiveActions ( MenuManager menu ) { } private void addKeyboardShortcuts ( MenuManager menu ) { } private MenuManager createHelpMenu ( ) { } private void fillToolBar ( ) { } private void fillShortcutBar ( ) { } public void dispose ( ) { } public boolean isContainerMenu ( String menuId ) { } public boolean isWorkbenchCoolItemId ( String id ) { } private void makeActions ( ) { IPartService partService = getWindow ( ) . getPartService ( ) ; WWinKeyBindingService keyBindingService = getWindow ( ) . getKeyBindingService ( ) ; IWorkbench workbench = getWindow ( ) . getWorkbench ( ) ; newWizardAction = new NewWizardAction ( ) ; keyBindingService . registerGlobalAction ( newWizardAction ) ; ISharedImages sharedImages = workbench . getSharedImages ( ) ; <START_BUG> newWizardDropDownAction = new NewWizardDropDownAction ( workbench , newWizardAction ) ; <END_BUG> newWizardDropDownAction . setImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_NEW_WIZARD ) ) ; newWizardDropDownAction . setHoverImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_NEW_WIZARD_HOVER ) ) ; newWizardDropDownAction . setDisabledImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_NEW_WIZARD_DISABLED ) ) ; importResourcesAction = new ImportResourcesAction ( workbench ) ; importResourcesAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_IMPORT_WIZ ) ) ; importResourcesAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_IMPORT_WIZ_HOVER ) ) ; importResourcesAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_IMPORT_WIZ_DISABLED ) ) ; exportResourcesAction = new ExportResourcesAction ( workbench , WorkbenchMessages . getString ( "ExportResourcesAction.fileMenuText" ) ) ; exportResourcesAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_EXPORT_WIZ ) ) ; exportResourcesAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_EXPORT_WIZ_HOVER ) ) ; exportResourcesAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_EXPORT_WIZ_DISABLED ) ) ; rebuildAllAction = new GlobalBuildAction ( window , IncrementalProjectBuilder . FULL_BUILD ) ; rebuildAllAction . setActionDefinitionId ( WorkbenchActionBuilder . rebuildAllActionDefId ) ; keyBindingService . registerGlobalAction ( rebuildAllAction ) ; buildAllAction = new GlobalBuildAction ( window , IncrementalProjectBuilder . INCREMENTAL_BUILD ) ; buildAllAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_BUILD_EXEC ) ) ; buildAllAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_BUILD_EXEC_HOVER ) ) ; buildAllAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_BUILD_EXEC_DISABLED ) ) ; buildAllAction . setActionDefinitionId ( WorkbenchActionBuilder . buildAllActionDefId ) ; keyBindingService . registerGlobalAction ( buildAllAction ) ; saveAction = new SaveAction ( window ) ; saveAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVE_EDIT ) ) ; saveAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVE_EDIT_HOVER ) ) ; saveAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVE_EDIT_DISABLED ) ) ; partService . addPartListener ( saveAction ) ; saveAction . setActionDefinitionId ( WorkbenchActionBuilder . saveActionDefId ) ; keyBindingService . registerGlobalAction ( saveAction ) ; saveAsAction = new SaveAsAction ( window ) ; saveAsAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEAS_EDIT ) ) ; saveAsAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEAS_EDIT_HOVER ) ) ; saveAsAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEAS_EDIT_DISABLED ) ) ; partService . addPartListener ( saveAsAction ) ; saveAllAction = new SaveAllAction ( window ) ; saveAllAction . setImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEALL_EDIT ) ) ; saveAllAction . setHoverImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEALL_EDIT_HOVER ) ) ; saveAllAction . setDisabledImageDescriptor ( WorkbenchImages . getImageDescriptor ( IMG_CTOOL_SAVEALL_EDIT_DISABLED ) ) ; partService . addPartListener ( saveAllAction ) ; saveAllAction . setActionDefinitionId ( WorkbenchActionBuilder . saveAllActionDefId ) ; keyBindingService . registerGlobalAction ( saveAllAction ) ; undoAction = createGlobalAction ( UNDO , "edit" , true ) ; undoAction . setImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_UNDO ) ) ; undoAction . setHoverImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_UNDO_HOVER ) ) ; undoAction . setDisabledImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_UNDO_DISABLED ) ) ; redoAction = createGlobalAction ( REDO , "edit" , true ) ; redoAction . setImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_REDO ) ) ; redoAction . setHoverImageDescriptor ( sharedImages . getImageDescriptor ( IMG_TOOL_REDO_HOVER ) ) ;

Fix:
newWizardDropDownAction = new NewWizardDropDownAction ( window , newWizardAction ) ;